Evaporator



www2@ @cem ML l Q22@ C. W, DYSQN 'ZET AL A EvAPoRA'ToR Originl- Filed March 25 ;920 um ,nshea 527mm -Inr Pressar @eco M 3923.,

C. W. vDYSON ET AL EVAPORATOR Original Filed March 26 in ligure l;

llatentediflee., lill, '119232 unirse sir/arias loraricir.;

CHARLES DYSON, 0F UNITED STATES NAVY, AND MILTON C. STUART, OF ANNAJPO- L'IS, MARYLAND,

ASASTGNORS TO ANDALE ENGINEERING COMPANY, OF PHILADEL- J'EHIA, EENNSYLVANIA, A CORPORATTON OFF PENNSYL'VNA.

nvasoaaron.

Original application led March 26, 1920,`Seria1 No. 369,114.

Divided and this application filed.

August 10, 1922. Serial No. 580,990.

4declare the following to bea full, clear, and l exact description of the invention, sucli as l w'll enable others-.skilled inthe art to which it appertains to make and `use the saine.

This invention relates to evaporators, esv pecially adapted for use aboard ships, and 'has'for its object-.to provider. means for this purpose which will be comi'iai'atively inexpensive to manufacture and more elli-- cient in actionthan 'those heretofore proposed.. i l

4lilith-these'and other object-s in view, the invention-cons'sts in the novel details of construction andcombinatioiis of parts more fully hereinafter disclosed and particularly pointed out in the claims.

This application is a division of our copending application for evaporators, filed March 2G. 1920, Serial No. 369,114, now -Patent Number 1,440,723. l

Referring 'to the accompanying drawings foi'minga part of this specification, in which like numerals designate like parts in all the y viewsi i Figure -1 is a diagrammatic elevatonal view `partly in section of a first effect evaporator joined to 'a second effect evaporator, made in-aocordalnce withthis' invent'on;

Figure 2 is a sectional lplan view of they second effectevaporator shown in Figure 1; Figure isa side elevational AView, partly in section. of the -second effectI evaporator shown iii Figure 2;" Figure 4 is a ,detail sectional view illustrating'onevof the. coiled tubes in position.; Figure 5 -'s a plan view of the parts shown Figure 'G is an enlarged lsectional detail. view of lone of the dra-in plugs;A Figure 7 isa sectional view of a. micrometer, valve employed: in Athisinvention; and Figure 8 is a sectional view taken on. the

line 8,-8iof Figure 7, looking in the direc? tion of` the arrows.

Referrin numeral 1 indicates the outer shell of a first effect evaporator, 2 a high pressure steam pipe, leading directly from the boilers, not' shown, 3 a micrometer valve illustrated indetail in Figures 7 and 8, 4 adrain pipe provided with a micrometer valve, 5, and 6,

particularly to Figure 1, .the

7, 8, 9,' '10, 1.1' vand 12 indicate. partitions between the outer wall 13 .and the inner Vwall lll'of; the door -likermembers 15 with which vthe first effect evaporator 1, as well y as the second 4effect.evaporator 54 are provided.A @ne of these said door like inem-V bers 1'5 is conveniently secured to the shell '5'4- as a-t 16, and athe other is secured in a similar `inaniie r,inotV shown, tothe iirstv effect shell 1. Y l i On the interior of'ea'chof the shells 1 V` and '511 of' the evaporators, there are pro vided a plurality of steam conveying lcoiled tubes. These tubes may beas iininerous'as desired, and are preferably arranged in horizontal'rows. Thre'ciofthe top rows of these tubes are numbered'l, 18, and'19,and

are best shown inl Figures 2 and 8., The

.open ends ofveachof theitubes communicate with' channels that are vformed iii the doors.

15 separated by the'lpartitions numbered 6to 12. .The top channels in the evaporato'rs land 54 are; numbered 420, the next lower channels are numbered 21 'and the next succeeding channels are numbered 22. That is to say,as will be understood from Figures 3, l and 5, a ygiven coil or tube has its upper end 23 opening into an upper channel such as` 20 above a partition such. as 6, and the .lower end of said `tubeopens into a lower' channel such as 21 below said p'artii i tion 6. But, as'ab'ove stated., it is. preferred to provide'ior each of the channels 20 and 21 .a plurality of coilsj-oi" convolutions as best indicated in `Ii`igure2, and'in such case..

all their upper open ends 23 will be joined vin parallel with an upper channel while all their lower ends vwill be joined in para'llel 4with a lower channel. n

@n the. other hand, said channels or steam fices and said coiled tubes.

` lit therefore follows that i ieo Aco'il elementsl to 12 have no'cominunication with each other exceptthrough drain oriy f we count, from the top` row' down, the said 'convolutions evidentvvhen we that the steam .enteri ing the end/523 off-.the lcoil 17,".i`or example, in the channel 20, will be vdischarged ,frein the ends 241 of-saidifcoil's'17, int? the'l next lower channel 211, Whence'the said steam im- .'mediately enters' the upper' ends offt'he' coils 18, and dischargesfronithe lower ends' of 22 and so o'ndovvnto thelast channel in" the first effectv 1, .or inthe lsecond effect. 54.- TheJ-coilsor -tubes are firmly held in` posisaid coils into the succeeding lower channel tion by their ends being rolled. or "expanded into the Wallslla of each of the doors 15,

'and are attached at.. their rear portions to a plurality of vbraces '27, some ot, ivhich, are' provided with the flanged platesv p'referab-ly *I 270, see *`iguresf2 and-3, and which braces are secured tov the. doors 15. bythe tierods 28 ,as illustrated.A So yfirmly do said lbraces and tie rods hold the coils that therear porvtionsof the latter .are no't'mfoved"v to substantial extent upon changes in temperai ture,A vand therefore, movements'A 'duezfv to" ex-y 25.. l l i vently' appear. As above stated', theste'am pensionsl and contraction are ltalren'iip hyp,

the convolution of the-coils', aswvill'prespasses ,throu hthe coils in'eachchannell in i `multiple, an passes through' said 4co'ils,"vvhfen i eonsideredin vertical rows i-ni series, but as the 'steam4 flows through the successive coils,

part o it is .condensed in each coilhdue toA l"the loss of heat to. the Water beingr'evapo-l rated, in the spaces 'of each evaporator l1 andy .54. In order to drain off this 4oon-4 densed steam there lisi-provided in .each chan- Vnel 6l to-12 the drain in Figures 1 and 6.

lug" 30,as best shown 4 ach.l plug is provided with a'hole 31, so small that no appreciable amount of live ,steam can.' escape therethrough,` While at'the lsaine time the. con;

:Sdensed steam o rvaterv can be forced through saidholeby the pressurleofthe live steamA .in the coils, saidl plugsN 30 arepreferably.ilo,- fcatedl liir depressions l32 lprovided inI theA channels, so that a Waterseal liormedby'A said condensedisteam will usually overlie each holel. `A plugll forcleaning vand inspection= Vpurposes may be` each plug'Oias illustrated.

It will be clear'. that "the condensedsteam,

through each 'plug 30 will 'drain' into thev channel next.below,until it reaches the drain pipe 4. Not only may 'high pressure steam be utilized in thefirst effect; evaporator 1,

through pipe 2, .butexhaust ,steam from any "convenient :Sou-ree or sources maybe led in through pipe 37. provided )vith'the micromre l .va iplained), ,that itissubstantially allv co`neter valveV 38 when it is"not ,desired toV yuse.

high .pressure steam. In either case,Ik the steam supply* torthepevaprator may be so ulated' lby adjusting' the micrometer densed in the coils, and therefoije,l only.co'n'- 'den'sed"steaii`i. passes out the drain pipe` 4,

provided overv ves 3 .and 5l (as ivill Fbe .presently ex-lv adjusted asl to prevent, it, explained -bel'ovml The'eonstruetion 'of t e"iiiieroin'e e valves' 3,6, and`38,`-as\vell aslothers Wliichwillbe" .meiit ioned hereinafter,- willlfbe clearfrom "'.Figures 7 and Spar/herein` ,89j represents a stean'ipassage to be" ,controlledflltl fa I disky movable across said passagegfand .provided withy the expandingcurvedcrescent-,shaped slot or opening l1 adapted toadjustably .throttle said' passage represents' a s'temated disk41 a'fpointer, coacti-ng vvitiithe pointer 44;, )any desired' proportion;-o the .area of the 4passage ,3Q can fbe, cnt hland therefore, th'e steam vniay beLthrottled'fWith certainty to an'y vdesired degree. {lhepe-j 'so ,gradiiations -oii the disk -iiians ,for moving, said pointer. ovcr'said'di'slt/l. "Itis evident that by properflyfadjustiii i'. the

euliarl curvature of the tubes orf-colssuch'- as 17, 18 and -19 in both theliist andi-'second effect Ievaporato'rs Iconstitutes ani-important teatjure of this invention in thatsaid. curva# ture 'causes afmoregetlicient scalingactin )ratei-, y soon forms thereon but. owing to'4 each coilbeine.continuouslyv curved and reversely lcurve y ,having ai'iyvstraight portions at'alha is evif dent, that.' any expansions" or contractions,

from` end to end, Without y due .to changes in temperature Will vaid in l frequent looseiiiiigs-.o'f'-the scale at ,every pointof `ea cl i-coil. The scaleloosening eff fe'ct i-s j' :furthe-i"` .m'ulti plied 'by ,securing the coils .li'rmly zigaiiistbodil'y.--inoveinent by means of' the braces 'and rods 2 7 and 28,'as' above explained; In other words, owing to vthe peculiar curvature of these saidcoils theycan bexinade very muchA longer than heretofore, and a4 relatively 'slightcha'iige in teinpe'raturefwill produce a relativelylarge movement, or' change, in ci'irvature of said,

coils, and thus :the scal'efis broken off vwith, a frequeney'and an efficiency' heretofore un-4 attained.- f

effect evaporator 1 'niaypass' ol-tthrough the pipe 45, having the micrometer valve 41Q-,tothe 'distillery-not, shown. 0r, allora l.second effector lower pressure eva orator 54-.isconstructed substantially like tie first 'lefeet evapoiator andtherefore' duplicate- The vapor from the sait'ivater iii the lfirstI @erases in; each evaporator are designated, by

similar numerals.

The operation off'said' second eect evaporatoris similar to said first effect apparatus,

the maindifferences being the provision of'- the partition' 53 which" separates' the vapor delivered throughithe pipe 51 from thatdeli'v'ered through pipe 55,ajs will presently appear.' `VThe'vapors fromthe sea .Water conf.

tained in' the space 1,29 of said second eect' eva orator vma Abe carried-off `b any 'suit- P ,y Y

able fmean's similart'o the pipefifp in the firstV effeot'evaporator, but not illustrated.`

i -crometer valve 52 that ,they Will all be substantially condensed bythe time they. reach A the channel 57, in said secondv effect evaporator ivhence their" condensate maybe drained' off through the micrometer valve 58 and 1pipe 59 to thedistille'rs. It tllusvrev sults that `\vhether the evaporated sea Water is ledl directly to'tliedistillers through the pipe Lf, or is further lcarried through the second leffect evaporator'to rob `it of its heat, it does not contaminate any condensed steam,

` nor is there any loss of said evaporated Water in ther-procedure,

Theconde'nsatefrom the first effect apparatus 1 is'vearried by the pipel to the low-.

est coils 60 ofthe secondeffect' 54,- vvhich'-coils may bejoined in series as shovvn, andsaid condensate is then drained off through the micrometer valve -61 n-an'd pipe. 62 to.- the fresh Water tanks..

66 represents al.microm'eter'valve'and 63 a drain to aftrapfnot shovvn'but which may be maintained at atmosphericpressure; 64

ind'ica'tes a micrometer valve and 65 a pipe conveying high pressure steamv to the pipe 55. S The operation of this evaporating systeinivill be clear from tlie foregoing but may be briefiy summarized as follows:

Sea Water being placedin the first effect f evaporator .1, and in low pressure evaporator heat it may possess.

A 54, high pressure vsteampmay be conveyedthrough-the pipe'I 2 or auxiliary exhaust f steamfrom donkey engines, or otherauxillary power plants, maybe conveyed into said first effect evaporator through pipe 37. In

either case, the 'micrometer valves 3 or- 38 maybe so adjustedtli'at all the steam entermg said evaporator 1 and passing through its coils 1T- 18,19, etc., Will be condensed by i the time it reaches the drain pipe 4, and furw therthe micrometergvalve 5, in said pipe 4, muy be so adjusted that any steam that may pass into said pipe 1Will be throttled off. The h ot fresh' Water thus' produced is carriedV over to the second effect ,oflow 4pressure evaporator 54 and through ythe coils 60, in order to' abstract any surplus From the coils said condensate is drained 0E through the valve 61 and pipe 62, to the fresh Water tanks.k

At nov time is any y,fresh Water condenthe first I'effect evaporator maybevcoinducted through thel pipe 4 8, the steam separator 50,.themi crometer*valve 52, and coils 17,

18, 119, -etc.,:l1of the'v secondedect evaporator `to andthrough'the valve 58.

- This saidvapor thus evaporates an additional quantity of saltwvaterin the low'pressure Lapparatus-54, and Iatthe same time, all the salt- Water condensate'is saved, as above 'pointed 'o`ut, by passingy it` through the'.

pipe 5'9Qt0 the distillers. Y

In addition to'rth's salt Water vapor aux-l ilary exhaust .steam may be simultaneously, orgindependently used in said evapora't-or- 54, lby-"passing said .auxiliary steam through` fthe coilsl 17, '118,' 19, etc., loca-ted on theright hand'si-de' ofthe partition 53, as seenin Figure, 15,' and located ,above said .partition v53,-asi-seen in Figure 2. Saidl 'auxiliary steam isf'conven'iently introduced through pipe '55' and Avis so tlirottled by a `micrometervalve 56 as to cause it to all -be condensed by the time yit reaches valve 66. lfhoweveranyportion of it remains luncondensed When valve f. 66 is reached, said valve may be soa-djusted as to throttle-off the live steam, whereupon the con- 'densed steam or Water Will pas's through the pipe 63 to any convenient 'trap main tainedat atmospheric pressure.

The partition 53, inthe second' effect evaporator prevents the condensatesi' passing through the pipes 51` and 53, from mixing. Owing to its possible contamination with oil the condensate passing through the pipe 63v is not mixed With that passing through the pipe 62. Should it be desired to'employ high` pressure vsteam in the second effect evaporator, such' may be introduced through .the pipe 65, and valve 64,and in suchcase said secondeffect evaporator will operate inso far as its Icoils Aon the right hand side of the partition 53 are concernedin the same manner as does the first effect evaporator.

O n the other hand,\if it is desired to emi i ploy live steam simultaneouslywith the con densedA vapor through pipe '51, itl can also be employed*that Way. ln other Words, [it

f will be observed that the second effect evapf orator may be run independently, precisely as is-the'flrst effect evaporator, or it may be run simultaneously-with the employment 'of vapor from the' first effect evaporator --through pipe 51. 1

lt will noW'be clear that Withcthe foregoing evaporator system, the following advantagescontributing to its high eliciency meansv for. controllingthe. operation .as Well '-for the end of another coil.v

. coils, so that-.only condensed steam may es p-cape from the coils, thus insuring@ highly 'a means for utilizing' low pressure exhaust 1. One vis enabled to provide a .relatively very long,

through the coi.l s; v. 42.. The fmicrometer valvesalford .a` ready as the capacitywofjthe system.v In fact, the

- capacity of the system may bevirtually controlled by lthe-"valves B and 3.8.'

3.' The drainl plugs 30 constitute a meanse placed' so near together that the expanslon of a tube in one hole `changesthe dimensions for draining off the-.condensatelrom 'each coil as itis formed so' that only dry steam enters the coils. When desiredautofmatic viioat valves such as 70, see Figure 6, may be employed in connection with theopeningsl .31, but ln'practice 4such v-alyes are not' found.v

tojbe necessary in many ca'ses.

4. rThe"micrometer valves`5,"58 and 66 constitute a means for controlling the dise charge of`condensateffrom each-group oi?v eilicient heat exchangej 5. The pipe 4 constitutes a means for further abstrac-ting heat from the condensate from' the high Apressure steam, and thus still further .increases the params;

ptliciency; of the aps. 6. The pipe 55 and partitionl constitute steam in the same apparatus that ,'-is'hutilizl condensation of the steam, the use of traps..

ing W pressure vapor from said salt W'ater';

7. The pipe 65 and partition 53 constitute.l a means of using high pressure steam. in the,l

same apparatus that is using low pressure vapor from salt Water;

v8. Owing to *the .relatively long coiled tubes," the high velocity oft the steam, and to'l the micrometer' valves insuring a complete or drain pots may be done aryay with.

9. Owing to the continuously curved pipe' in the coils, and the peculiar'bracing and holding means preventing the bodily movement of said coils,the contractions' andex pansions incident to the changes in temperature greatly aid in keeping the coils free from scale.

IL Will be observed that the. drain plugs 30 are omitted from the lowest row ofcoils in each evaporator, so that the lowest rovT of coils will conduct all the `Water that -is condensed in 'the'upper coils.

Further, it Will be observed that the low est row of coils maybe arranged in series instead of in Figure 1.

This will expedite' the further cooling of the condensate. In all cases, the doorsl, and their attached coils may be readily removed Without disturbing the steam connections. Further, owing to the fact that the coils are unusually long, and owing to their peculiar curvature, the manufacturer is enpath of? travel-, for the s tearnl y control the pressure and temperature ofthe parallel as is illustrated in'` abled to locatethe'ends of the coils inthe plate 14 of .each door'` farther apart than has beenheretofore possible, with the. same caf..

pacityof apparatus, and this results in the" important advantagethatWhen, the end of the one coil-is being expanded,` it doesV not distort or change the dimensions of the hole,

rn other. words, the hues in rhe'wauie accurately fit the coils' even after repairs which lisnot the-casevphen the-holes are of a neighboring hole.

nel, yetlthey may be, desired,'arranged in series. or in any other "'connect1ons 'which willbest suit the requirements for .coolingr` ,1

the condensed-steam toa point Where it may be discharged Withoutthe loss-.ot` vapor.4

The graduations, not'shown, on the dis'k'; i

43, may b e determined by acalibratiolrniade :1t-various points with various portions or thefslot 40 in the disl,fo'r bothjwaterfand 'stea-m. The micrometer valves in thesteanl pipes control the capacity of the evaporai tors While the said valves in the .drain pipes discharged condensates.` l )It is obviousthat those .skillednin the vart niay'vary the details of thexcons'truction as Well as the. 'arrangement ofparts without departing' from Ithe spirit out the invention, and therefore, we do not Wish to vmaybe required by the claims.'- A jl What is claimed isi f' 1..In an evaporator system the combinatio'n of a shell, adapted to contain'the liquid t0 lie-evaporated; means comprising a coil, adaptedtocontain steam in said shell; a pair bf channels located` one above the other and provided with drains for passing a liquid bygravity from one into the other connected to said means; a pipe for conveying 4steam vto'said means; and a micrometer valve 1n 'said pipeiadapted to so'throttle said steam yas to' cause substantially all of itto condense.- .in' said' channels before leaving said shell,

substantially as described.'4

2. ot a shell adapted tocontain salt water; means to impart heat to said water comprising a plurality of coils .of'pipe' adapted to receive steam;l ajplurality of channels' located oneabove the. other and provided with drains for passing liquid from one into.

the otherI ,ccnnectedJto said means; a steam supply connected vto said means; a drain `pipe leadingirom said means; and al valve 'in said steam supply adaptedfrtosothrottle said supply as to cause substantiallyall of `v y said steam to condense before entering said drain pipe, substantially as described. s

"be limited to the above' disclosure ircept as 4liian evaporatorsystenithe-combination revises l 3. ln an evaporator system the combinah tion of a shell adapted to contain salt water; means to impart heat to said Water comprising a. plurality ot continuously curved coils ofpipe adapted to receive steam; a Ipair of channels with which each coil is connected, said channels located one above the-other and provided with drains; a steam supply connected to said means; a drain pipe leadingl trom said means; a valve in said drain pipe; and av valve in said steam supply adapted to so throttlesaid supply `as to cause substantially all of said steam to condense before entering said drain pipe; substantially as described.'

il. ln an evaporator` system the combina-A tion ot a shell adapted to contain salt water; means to impart heat to said Water comprise ing a plurality of channels and continuously curved coils of pipe adapted to receive steam; drains connecting` said channels; a

steam' supplyconnected to said means; av

drain pipe leading from said means; means to prevent the bodily movements of saidv .curved coils of' pipe during changes fof tempeiature but readily. permitting changesv in the curvatureof said pipe; and a valve in said Asteam supply adapted toso throttle said supply as to cause substantially all of said steam tocondense' before entering vsaid drain pipe, substantially as described.

5,. ln an' evaporator system, the combination of a shell adapted to contain saltwater;

pipe to convey away the vapors of said Water; vmeans to impart heatto said Water comprising a plurality of lcoils Vlorp pipe adapted to receive'steam; a pair of channels locatedoiie above the other provided with drains joined to veach of said coils; a steam supply connected to said means; a drainpipe leading from said means; a second shell adapted to contain salt Water; evapora-ting Jfor conveying off the vapors formed in said -evaporator;a second effect evapora-tor; connections Aprovided ivitha micrometer valve between sai'd means and saidseeond effect evaporator; and connections between said 'drain pipe and said last .named evaporator,

substantially as described.

7; ln an evaporatorsystem the combination et a lirst effect evaporator comprising a plurality of evaporating coils; a plurality scribed. f

ot channels located one above the other with which said coils are connected; drains leading;` from the supply channels to the lower' channels a ste'am supplyfor said'evapoiator; amicrometer valve in 'said steam supply; a

'-drain pipe for the condensed steam; a micrometervalve in said pipe; means for conveying, ofi tl1e. vapors formed in said evaporator; a second eiiect eif'a-por'ator comprising' a pluraiity of sets of evaporating coils; connectioi'is'provided with ay micrometer valve 'between said means and` one set of coils-in. said second effect evaporator; connections betweensaid drain pipe and said last named evaporator; and means toV supply. steam to vanot'lierset of coils in said secondeiiect evaporator;substantially as de' 8. ln an evaporatorsysteinf7 the combination ot a1rst ciilectI evaporator; a steam" ,supply .for said evaporator; a dra/in pipe For the condensed steam; ,a p ipeto .lead- .oii' the Water evaporated; second effect evaporator; t\v.o xsets ofl coils in said last named evaporator;-means to convey a Aportion of said evaporated water throughone not said sets of coils; means to convey steam through another ot said-'setsfotl coils; and means toi connect said drain pipe to said second effect evaporator, substantially as de- 1 scribed. i

9. lnfan evaporatorsystem the combina- .tion' of a first effect evaporator; a steam supply-for said evaporator; a micrometer valve in. said supply; a fdrain` pipe `tor the condensedsteam; a micron'ietervvalve in sai`d pipe; a pipe to lead ott the water evaporated; a second effect evaporator; tivo. sets.

- ot coils in said last named evaporator; means to convey a porltion off said evaporated Water through one ot'said `sets of coils; a

`micrometer valve in said means; mea-ns to convey steam through another o't said sets of coils; a micrometer valve -in said last named' means; and means to connect said drain pipe to lsaid second effect evaporator, substantially as described.

10. In an evaporator systemt'he combinationof an.`evaporator comprisingi a pluralityv of channels located. thefone above' the'other and provided with drains adapted to pass liquid 'from an upper to a lower steam to said'ievaporator; independent means to supplylow pressure steam to said evaporator; and a micrometer valve in each 'of said steam supplying means' adapted to sothrottle the steam as to cause substantially all of it to lcondense before leaving the evaporator, substantially as described.

ll. ln an evaporator system the combination' ,of an eiiapoiiator; means to supply high pressure steam to said. evaporator; idependent means to supply low pressure steam to said evaporator; a mioronfie'ter TUl itil

iis

channel; means to supply high pressure ISO valve in each of said-steam supplying means adapted to so'throttle the steam -as'tdca'use lsubstantiallyalflfof it'to condense before leaving the evaporator; an' independent means to supply hot vaporsto said evapo rator; avalve controlling sa-i'd last named. means; and n 1e` a .ns'` for preventing., said.- vapo'rs from mlxl'ng with the steam 1n Said' to the same set of coils of said evaporator;

the other set of coils; an valve controlling said last named means;-

a micrometer valve in each'of 4said steam supplying means adapted to'so. throttle-.the

steam as to cause vsubstantially` .all'of itin condensebe-fore leavingl the evaporator; yindependent means' to suppf hot vapors to a micrometer substantially as 'described 13.l In an evaporating`sys'tem, a coil havinga continuousand reversed curvel from' end'to end; and means to prevent' changes in temperature from. bodily movingl isaid, coil While permitting ready'changes in curvature, whereby the cracking of any scale that may be formed therein is facilitated, substantially as described.

14. In an evaporating system, a coil -ha ing a. continuous v.and reversed curve from end to end; means to p-revent changes in temperature from bodil 'moving said .coil vvh-ile-permittingready c anges in curvature, whereby the cracking of any scale that may be formed therein is facilitated; a channel with which one end of said coil communicates; another channel Withwhichthe other end of said coil communicates; andl means .for 'admitting steam to said first named channel, substantially as described.

A15. In an evaporator the combination of a plurality of channels located one above the other and each provided with ,a perforated drain plug; and. steam coils each communicating with said channels in pairs, substantially as described,

1G. In an evaporator the combination'of a plurality of channels located one above the other and provided` With depressions and cach provided also with a draining means located in a depression; and steam "coils communicating with said channels, substantially as described.

17 In an evaporator the combination of.av plurality of channels located one above the other, and provided with draining means by Which one channel drains into another;

- Leaaeas `ani'inspectim'ocv'lp'enin'gi closed byl a plug 'located 'above sai draining means; and steam co-i'ls communicating with said channels in r pairs, substantially as described.

1 8'. In, an'- evaporator the combinationof means for supplying steam; means for cond ensing said steam"; channels 'located l one above 'another in #which said condensed vsaid Steam 'asto cause itto bev substantially .all condensed before leaving the' system, substantially asdescribed 19. Inan'evaporator the combination of mean sconiprising aI coil element; means for Channels located` one above another tok one of which-eachfend'of said coil is connected;

meanfor draining 'by gravity liquid frein one of said' channels into the other; and

means for so`thro'ttling said steam asv toi `cause 'it to be' substantially all condensed vvhenlit leavesthe system, substantially as described.

.20. In `an evaporator the combination 'of a container for the liquid to be evaporated; a pluralityof coil elements in said container; a lurality of channels located one above the l`passingsteam through said coil; a pair of l I.

auf

et er to Whichth'e ends of said coil elements are' connectedin pairs; drains from an upper channel into a lower channel; means to pass steam into 'said coil elements and channel-s; and means to draw oft' the liquid condensed in` said channels, substantially as described."

, 21. In an evaporator the combination of means to supply steam; means to throttle said steam; means to separate at a plurality of pointsv the condensed from. the uncondensed steam as fast as it is formed 'means to collect the condensedsteam from all of said points; and means to draw off'the condensate thus collected, substantially asdescribed.

22. In an evaporator the combination of a container for the liquid to be evaporated;

means to heat said liquid comprising a plurality of o oil elements located one above the other; .means to supply steam to said elements in series means to segregate the steam condensed in sai'd first named means ata plurality of points located one ab'ove the other; means to drain vall of the condensate to a single point; and means to draw said condensate from the system, substantially as described.

In testimony whereof We aliix our signatures.

cuantas vv. Dyson. Minton c. STUART. 

